Polishing Pad with Segmented Polyurethane and Elastic Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional polishing pads face challenges in maintaining high-precision flatness during polishing processes due to flexibility leading to roll-off and potential scratches, with existing multi-layer structures either being insufficient in flexibility or increasing production complexity and cost.
Innovation Solution
A polishing pad comprising a flexible plastic sheet with higher compressibility and lower A hardness, paired with an elastic body having specific compressibility and A hardness ranges, both with sufficient thickness to absorb surface irregularities and support the polishing surface evenly, reducing roll-off and scratches.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a flexible plastic sheet is used for polishing, then polishing liquid can be accumulated and the surface can conform to irregularities, but the pad deforms easily causing roll-off and reducing flatness
Solution Approach 1:
The polishing pad is divided into two distinct layers: a flexible plastic sheet layer (0.2-2.0mm thick) that provides conformability and absorbs surface irregularities, and a hard support layer that maintains structural stability and prevents roll-off. This segmentation allows each layer to perform its specific function optimally without compromising the other.
Solution Approach 2:
The invention uses a composite structure combining two materials with different mechanical properties: a flexible plastic material (such as polyurethane) for the surface layer that provides cushioning and conformability, and a harder support material for the underlying layer that provides structural integrity. This composite approach resolves the contradiction between flexibility and stability.
2Manufacturing precision
If a hard plastic sheet is used instead of flexible plastic, then roll-off is suppressed, but scratches occur on the object surface due to polishing particles
Solution Approach 1:
The polishing pad is segmented into a soft flexible layer in contact with the workpiece and a hard support layer beneath it. The flexible layer acts as a cushion that prevents polishing particles from directly scratching the object surface, while the hard layer provides the necessary structural support to prevent roll-off.
Solution Approach 2:
The flexible plastic sheet serves as an intermediary layer between the hard support structure and the object being polished. It mediates the interaction by absorbing shocks and preventing direct contact between hard polishing particles and the object surface, thereby reducing scratches while maintaining flatness.
3Manufacturing precision
If a three-layer structure is used to suppress roll-off and scratches, then flatness improves, but production process becomes complicated and costs increase
Solution Approach 1:
The invention extracts and eliminates the unnecessary middle support layer from the traditional three-layer structure, retaining only the essential two layers: the flexible plastic sheet layer for scratch prevention and conformability, and the hard support layer for structural stability. This simplification reduces production complexity while maintaining the desired flatness and preventing roll-off.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively suppresses scratches and roll-off, enhances flatness by ensuring even pressure distribution and absorption of surface irregularities, while maintaining flexibility and durability through controlled compressibility and A hardness ranges.
Implementation Method 1
the flexible plastic sheet has a higher compressibility and a lower A hardness than those of the elastic body
Implementation Method 2
an elastic body joined on a surface of the flexible plastic sheet on the opposite side to the polishing surface
Data Source
AI summary
A polishing pad which suppresses occurrence of a scratch or a roll-off on an object to be polished so that flatness is improved is provided. A polishing pad 1 is comprised a polyurethane sheet 2 having a polishing surface P for performing polishing processing to an object to be polished and an elastic sheet 3 having elasticity joined on a surface of the polyurethane sheet 2 on the opposite side to the polishing surface P. The polyurethane sheet 2 is set higher in compressibility than the elastic sheet 3, and is set lower in A hardness than the elastic sheet 3. The elastic sheet 3 is set at 1% or more in compressibility, and is set at 90 degrees or less in A hardness. Further, both of the polyurethane sheet 2 and the elastic sheet 3 are formed to have a thickness of 0.2 mm or more. The flexibility of the polyurethane sheet 2 is exerted during polishing processing so that the polyurethane sheet 2 deforms to press the polishing surface P approximately evenly on the object to be polished.